Whatever you think of folk music, there's a lot to be said for a festival where the major form of antisocial behaviour is the use of folding chairs that block people's views. Normally the most disturbing sights at the Cambridge Folk Festival, which comes around again this week, are the long-term effects of a real ale diet.

So it was all the more unsettling, a few years ago, to witness a flash of genuine ugliness. As the crowds trudged off at the end of the evening, a group of inebriated men treated their fellow festival-goers to a ditty about "Sambo". Sung unaccompanied at communal events, passed on without being written down, songs like these are a kind of folk song, but not the kind that most folk enthusiasts want to hear.

For them, musical traditions are currents that flow into each other across the continents. The gospel singers, reggae acts and Malian kora players who have played at Cambridge affirm how British folk music has embraced its own vision of globalisation. But after more than half a century of the modern folk revival, the question at its heart remains unresolved: how should the English go about being English? Backward-looking as they may be, folkies were ahead of their time, facing the English question long before the English rediscovered their flag.

The question has become edgier in folk music circles thanks to the attentions of the British National party, whose chairman, Nick Griffin, proclaims his love of traditional music and which offers folk compilations under its Excalibur brand. As its mission statement affirms, folk culture and myth are at the heart of the BNP's vision.

It could hardly be otherwise: the party is a folkish nationalist group based on a belief that peoples have essences that must be preserved by keeping blood and culture mixed together, and separate from those of other peoples. The complication that Britain contains several "indigenous peoples" is resolved by invoking a northern European racial fellowship that embraces Celts and Anglo-Saxons.

A suitable counterblast to this rank leftover from 19th-century romanticism is at hand in the form of Lucy Wan, a ballad reworked as "folk-grime" by folk singer Jim Moray and rapper Bubbz. But not all folkies are convinced that rap is folk's way forward. Indeed, in the Show of Hands song Roots, Steve Knightley includes rap in his indictment of the impoverishment of English culture. He urges the English to "rediscover … their musical identity" because "we need roots".

Do we really, though? We need depth and we need substance, but we are not plants. At different times different peoples may need the strength that their roots give them, but at this point in history the English scarcely lack sources of support or enrichment. We enjoy affluence and access to knowledge far beyond the imaginations of those unknowns who created the ballads of the British folk canon.

People in England now have a world of possibilities at their fingertips. They are not an oppressed or an emerging nation. Heaven knows they need an awful lot of things in their lives that can't be bought in shops, but a new improved national identity is a long way down the list.

A sense of belonging will always be near the top, though, and the desire to feel part of a larger whole has always been an intimate part of the folkie imagination. Whereas folkish nationalism sees folk music as the culture of a people, some of the most influential strands in revived and reworked folk music have seen folk songs as the culture of "the people", a group defined in opposition to their lords and masters, rather than to counterparts in other lands. The idea of connecting with the people still strikes chords – and folk's substantial communist heritage still seems to be regarded as perfectly unproblematic. But the vision has faded and what union leaders used to call "this great movement of ours" halted long ago.

For those looking for something to belong to, there is still England. Whether that's what the English really need is another question.